Generally, a power converter includes a capacitor module for smoothing DC power, an inverter circuit for converting between DC power and AC power, and a control circuit for controlling the inverter circuit. In recent years, it is desired to miniaturize the power converter. Especially, in fields of a hybrid vehicle and an electric vehicle, it is desired to mount a power converter in the smallest space especially in an engine room outside of a cabin, and therefore further downsizing is required to improve mountability to a vehicle.
Further, an operating time and an operating condition (a high output torque condition) of a motor to be used as a driving source are likely to be expanded, and it is simultaneously required to increase a current and a voltage for power conversion. As a result, an instantaneous voltage increase (a surge voltage) is actualized which is generated when a power semiconductor element forming an inverter circuit performs switching operation.
A surge voltage level depends on a product of a parasitic inductance value between a capacitor module and a power semiconductor element and a current change during switching. Therefore, a technique described in PTL 1 suppresses a surge voltage by lowering an inductance of a bus bar. Further, noise flowing in a power converter is reduced by connecting a capacitor for removing noise to an input-side power source terminal,